Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 5.075
Filtrar
1.
Parasite ; 31: 37, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38963405

RESUMO

Enterocytozoon bieneusi is an obligate intracellular microsporidian parasite with a worldwide distribution. As a zoonotic pathogen, E. bieneusi can infect a wide range of wildlife hosts through the fecal-oral route. Although the feces of flying squirrels (Trogopterus xanthipes) are considered a traditional Chinese medicine (as "faeces trogopterori"), no literature is available on E. bieneusi infection in flying squirrels to date. In this study, a total of 340 fresh flying squirrel fecal specimens from two captive populations were collected in Pingdingshan city, China, to detect the prevalence of E. bieneusi and assess their zoonotic potential. By nested PCR amplification of the ITS gene, six specimens tested positive, with positive samples from each farm, with an overall low infection rate of 1.8%. The ITS sequences revealed three genotypes, including known genotype D and two novel genotypes, HNFS01 and HNFS02. Genotype HNFS01 was the most prevalent (4/6, 66.7%). Phylogenetic analysis showed that all genotypes clustered into zoonotic Group 1, with the novel genotypes clustering into different subgroups. To our knowledge, this is the first report of E. bieneusi infection in flying squirrels, suggesting that flying squirrels could act as a potential reservoir and zoonotic threat for E. bieneusi transmission to humans in China.


Title: Occurrence et génotypage d'Enterocytozoon bieneusi chez les écureuils volants (Trogopterus xanthipes) de Chine. Abstract: Enterocytozoon bieneusi est un parasite microsporidien intracellulaire obligatoire présent dans le monde entier. En tant qu'agent pathogène zoonotique, E. bieneusi peut infecter un large éventail d'hôtes sauvages par la voie fécale-orale. Bien que les excréments d'écureuils volants (Trogopterus xanthipes) soient considérés comme un ingrédient de médecine traditionnelle chinoise (comme « faeces trogopterori ¼), aucune littérature n'est disponible à ce jour sur l'infection par E. bieneusi chez les écureuils volants. Dans cette étude, un total de 340 spécimens fécaux frais d'écureuils volants provenant de deux populations captives ont été collectés dans la ville de Pingdingshan, en Chine, pour détecter la prévalence d'E. bieneusi et évaluer leur potentiel zoonotique. Par amplification PCR nichée du gène ITS, six échantillons se sont révélés positifs, avec des échantillons positifs dans chaque ferme, et un taux d'infection global faible, à 1,8 %. Les séquences ITS ont révélé trois génotypes, dont le génotype D connu et deux nouveaux génotypes, HNFS01 et HNFS02. Le génotype HNFS01 était le plus répandu (4/6, 66,7 %). L'analyse phylogénétique a montré que tous les génotypes se regroupaient dans le groupe zoonotique 1, les nouveaux génotypes se regroupant en différents sous-groupes. À notre connaissance, il s'agit du premier rapport d'infection par E. bieneusi chez des écureuils volants, ce qui suggère que les écureuils volants pourraient agir comme un réservoir potentiel et une menace zoonotique pour la transmission d'E. bieneusi aux humains en Chine.


Assuntos
Enterocytozoon , Fezes , Genótipo , Microsporidiose , Filogenia , Sciuridae , Animais , Sciuridae/microbiologia , Sciuridae/parasitologia , Enterocytozoon/genética , Enterocytozoon/isolamento & purificação , Enterocytozoon/classificação , China/epidemiologia , Microsporidiose/veterinária , Microsporidiose/epidemiologia , Microsporidiose/microbiologia , Fezes/microbiologia , Fezes/parasitologia , Prevalência , Zoonoses , Reação em Cadeia da Polimerase/veterinária , DNA Fúngico/genética , Doenças dos Roedores/epidemiologia , Doenças dos Roedores/microbiologia , Doenças dos Roedores/parasitologia , DNA Espaçador Ribossômico/genética , Animais Selvagens/microbiologia
2.
Nat Commun ; 15(1): 5803, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987241

RESUMO

Mammalian hibernators survive prolonged periods of cold and resource scarcity by temporarily modulating normal physiological functions, but the mechanisms underlying these adaptations are poorly understood. The hibernation cycle of thirteen-lined ground squirrels (Ictidomys tridecemlineatus) lasts for 5-7 months and comprises weeks of hypometabolic, hypothermic torpor interspersed with 24-48-h periods of an active-like interbout arousal (IBA) state. We show that ground squirrels, who endure the entire hibernation season without food, have negligible hunger during IBAs. These squirrels exhibit reversible inhibition of the hypothalamic feeding center, such that hypothalamic arcuate nucleus neurons exhibit reduced sensitivity to the orexigenic and anorexigenic effects of ghrelin and leptin, respectively. However, hypothalamic infusion of thyroid hormone during an IBA is sufficient to rescue hibernation anorexia. Our results reveal that thyroid hormone deficiency underlies hibernation anorexia and demonstrate the functional flexibility of the hypothalamic feeding center.


Assuntos
Anorexia , Grelina , Hibernação , Hipotálamo , Sciuridae , Animais , Hibernação/fisiologia , Sciuridae/fisiologia , Anorexia/fisiopatologia , Anorexia/metabolismo , Hipotálamo/metabolismo , Grelina/metabolismo , Grelina/deficiência , Leptina/deficiência , Leptina/metabolismo , Núcleo Arqueado do Hipotálamo/metabolismo , Neurônios/metabolismo , Neurônios/fisiologia , Masculino , Hormônios Tireóideos/metabolismo , Nível de Alerta/fisiologia , Feminino , Estações do Ano , Comportamento Alimentar/fisiologia
3.
J Anim Ecol ; 93(7): 862-875, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38831563

RESUMO

Food hoarding provides animals access to resources during periods of scarcity. Studies on mammalian caching indicate associations with brain size, seasonality and diet but are biased to a subset of rodents. Whether the behaviour is generalizable at other taxonomic scales and/or is influenced by other ecological factors is less understood. Population density may influence food caching due to food competition or pilferage, but this remains untested in a comparative framework. Using phylogenetic analyses, we assessed the role of morphology (body and brain size), climate, diet breadth and population density on food caching behaviour evolution at multiple taxonomic scales. We also used a long-term dataset on caching behaviour of red squirrels (Tamiasciurus fremonti) to test key factors (climate and population density) on hoarding intensity. Consistent with previous smaller scale studies, we found the mammalian ancestral state for food caching was larderhoarding, and scatterhoarding was derived. Caching strategy was strongly associated with brain size, population density and climate. Mammals with larger brains and hippocampal volumes were more likely to scatterhoard, and species living at higher population densities and in colder climates were more likely to larderhoard. Finer-scale analyses within families, sub-families and tribes indicated that the behaviour is evolutionary labile. Brain size in family Sciuridae and tribe Marmotini was larger in scatterhoarders, but not in other tribes. Scatterhoarding in tribe Marmotini was more likely in species with lower population densities while scatterhoarding in tribe Sciurini was associated with warmer climates. Red squirrel larderhoarding intensity was positively related to population density but not climate, implicating food competition or pilferage as an important mechanism mediating caching behaviour. Our results are consistent with previous smaller-scale studies on food caching and indicate the evolutionary patterns of mammalian food caching are broadly generalizable. Given the lability of caching behaviour as evidenced by the variability of our results at finer phylogenetic scales, comparative analyses must consider taxonomic scale. Applying our results to conservation could prove useful as changes in population density or climate may select for different food caching strategies and thus can inform management of threatened and endangered species and their habitats.


Assuntos
Evolução Biológica , Comportamento Alimentar , Mamíferos , Animais , Mamíferos/fisiologia , Classificação , Encéfalo , Sciuridae , Abastecimento de Alimentos , Clima
4.
Euro Surveill ; 29(25)2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38904114

RESUMO

BackgroundTo be better prepared for emerging wildlife-borne zoonoses, we need to strengthen wildlife disease surveillance.AimThe aim of this study was to create a topical overview of zoonotic pathogens in wildlife species to identify knowledge gaps and opportunities for improvement of wildlife disease surveillance.MethodsWe created a database, which is based on a systematic literature review in Embase focused on zoonotic pathogens in 10 common urban wildlife mammals in Europe, namely brown rats, house mice, wood mice, common voles, red squirrels, European rabbits, European hedgehogs, European moles, stone martens and red foxes. In total, we retrieved 6,305 unique articles of which 882 were included.ResultsIn total, 186 zoonotic pathogen species were described, including 90 bacteria, 42 helminths, 19 protozoa, 22 viruses and 15 fungi. Most of these pathogens were only studied in one single animal species. Even considering that some pathogens are relatively species-specific, many European countries have no (accessible) data on zoonotic pathogens in these relevant animal species. We used the Netherlands as an example to show how this database can be used by other countries to identify wildlife disease surveillance gaps on a national level. Only 4% of all potential host-pathogen combinations have been studied in the Netherlands.ConclusionsThis database comprises a comprehensive overview that can guide future research on wildlife-borne zoonotic diseases both on a European and national scale. Sharing and expanding this database provides a solid starting point for future European-wide collaborations to improve wildlife disease surveillance.


Assuntos
Animais Selvagens , Zoonoses , Animais , Animais Selvagens/microbiologia , Europa (Continente)/epidemiologia , Zoonoses/epidemiologia , Bases de Dados Factuais , Humanos , Ratos , Sciuridae/microbiologia , Ouriços/microbiologia , Coelhos , Camundongos , Vigilância da População , Raposas/microbiologia , Raposas/parasitologia
5.
Vis Neurosci ; 41: E002, 2024 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-38725382

RESUMO

Animal models of retinal degeneration are critical for understanding disease and testing potential therapies. Inducing degeneration commonly involves the administration of chemicals that kill photoreceptors by disrupting metabolic pathways, signaling pathways, or protein synthesis. While chemically induced degeneration has been demonstrated in a variety of animals (mice, rats, rabbits, felines, 13-lined ground squirrels (13-LGS), pigs, chicks), few studies have used noninvasive high-resolution retinal imaging to monitor the in vivo cellular effects. Here, we used longitudinal scanning light ophthalmoscopy (SLO), optical coherence tomography, and adaptive optics SLO imaging in the euthermic, cone-dominant 13-LGS (46 animals, 52 eyes) to examine retinal structure following intravitreal injections of chemicals, which were previously shown to induce photoreceptor degeneration, throughout the active season of 2019 and 2020. We found that iodoacetic acid induced severe pan-retinal damage in all but one eye, which received the lowest concentration. While sodium nitroprusside successfully induced degeneration of the outer retinal layers, the results were variable, and damage was also observed in 50% of contralateral control eyes. Adenosine triphosphate and tunicamycin induced outer retinal specific damage with varying results, while eyes injected with thapsigargin did not show signs of degeneration. Given the variability of damage we observed, follow-up studies examining the possible physiological origins of this variability are critical. These additional studies should further advance the utility of chemically induced photoreceptor degeneration models in the cone-dominant 13-LGS.


Assuntos
Células Fotorreceptoras Retinianas Cones , Degeneração Retiniana , Sciuridae , Tomografia de Coerência Óptica , Animais , Degeneração Retiniana/induzido quimicamente , Degeneração Retiniana/patologia , Células Fotorreceptoras Retinianas Cones/patologia , Células Fotorreceptoras Retinianas Cones/efeitos dos fármacos , Modelos Animais de Doenças , Injeções Intravítreas , Oftalmoscopia , Nitroprussiato/farmacologia , Feminino , Masculino
6.
AMA J Ethics ; 26(5): E429-433, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38700527

RESUMO

This essay plays out a few ethics reasons we have to reconsider what's really being marketed to us in some free offers that distract us from questions of ethical, cultural, and clinical importance, for example. Possible points of focus for bioethics as a field are related to antimicrobial resistance and stewardship.


Assuntos
Sciuridae , Humanos , Animais , Gestão de Antimicrobianos/ética , Publicidade/ética , Bioética
7.
PLoS One ; 19(5): e0302933, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38701075

RESUMO

Animals in urban areas often encounter novel and potentially stressful conditions. It is important to understand how wildlife cope with anthropogenic disturbance. To investigate this specific adaptation we live-trapped squirrels in two study sites in Warsaw: a forest reserve and an urban park and we estimated stress responses at three levels: long-term and medium-term stress (the level of stress hormones, i.e. cortisol and cortisone concentrations, in hair and feces) and acute reaction to human-induced stress (measured during handling with the aid of the three indices: breath rate, struggle rate, and vocalization). According to GLMM models no difference in the stress hormones level was found between the two populations. The only differences in cortisol concentrations clearly depended on the season, i.e. being higher in autumn and winter comparying to other seasons. There was no influence of sex, or reproductive status on stress hormones. Forest squirrels had significantly higher breath rates, suggesting they were more stressed by handling. There was no difference in the struggle rate between study areas, this index was mostly affected by season (i.e. being highest in winter). First-trapped squirrels vocalized less than during the subsequent trappings. Assumingly, during the first, and more stressful trapping, squirrels used 'freezing' and/or little vocalization, while during next captures they used alarm calls to warn conspecifics. Overall, we showed that the two squirrel populations differed only in terms of their breath rate. This suggests that they did not differ in medium-term and long-term stress in general, but they can differ in acute response to handling. This also suggests that both populations were similarly affected by environmental factors. The lack of clear effects may also be due to population heterogeneity. Thus, in order to assess the effects of anthropogenic stressors a broader range of indicators and diverse analytical methods, including behavioral analyses, should be employed.


Assuntos
Hidrocortisona , Sciuridae , Estresse Fisiológico , Animais , Sciuridae/fisiologia , Hidrocortisona/metabolismo , Hidrocortisona/análise , Estresse Fisiológico/fisiologia , Humanos , Masculino , Estações do Ano , Feminino , Cidades , Vocalização Animal/fisiologia , População Urbana
8.
Curr Biol ; 34(10): 2221-2230.e8, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38703773

RESUMO

Leprosy, one of the oldest recorded diseases in human history, remains prevalent in Asia, Africa, and South America, with over 200,000 cases every year.1,2 Although ancient DNA (aDNA) approaches on the major causative agent, Mycobacterium leprae, have elucidated the disease's evolutionary history,3,4,5 the role of animal hosts and interspecies transmission in the past remains unexplored. Research has uncovered relationships between medieval strains isolated from archaeological human remains and modern animal hosts such as the red squirrel in England.6,7 However, the time frame, distribution, and direction of transmissions remains unknown. Here, we studied 25 human and 12 squirrel samples from two archaeological sites in Winchester, a medieval English city well known for its leprosarium and connections to the fur trade. We reconstructed four medieval M. leprae genomes, including one from a red squirrel, at a 2.2-fold average coverage. Our analysis revealed a phylogenetic placement of all strains on branch 3 as well as a close relationship between the squirrel strain and one newly reconstructed medieval human strain. In particular, the medieval squirrel strain is more closely related to some medieval human strains from Winchester than to modern red squirrel strains from England, indicating a yet-undetected circulation of M. leprae in non-human hosts in the Middle Ages. Our study represents the first One Health approach for M. leprae in archaeology, which is centered around a medieval animal host strain, and highlights the future capability of such approaches to understand the disease's zoonotic past and current potential.


Assuntos
Genoma Bacteriano , Hanseníase , Mycobacterium leprae , Filogenia , Sciuridae , Animais , Mycobacterium leprae/genética , Mycobacterium leprae/isolamento & purificação , Sciuridae/microbiologia , Hanseníase/microbiologia , Hanseníase/história , Humanos , Inglaterra , DNA Antigo/análise , Arqueologia , História Medieval
9.
Sci Data ; 11(1): 517, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773139

RESUMO

This study investigates the adaptive strategies of the Alashan Ground Squirrel (Spermophilus alashanicus) in response to habitat changes, as rodents are sensitive indicators of ecosystem changes. Despite its ecological importance, the genome and microbiome of this species have not been thoroughly studied. This research fills this gap by presenting the first comprehensive metagenomic and transcriptomic datasets of the species. Transcriptomic data was collected from five tissue types, including heart, liver, cecum, muscle, and blood, resulting in the assembly of 72,156 unigenes. Metagenomic sequencing identified predominant bacterial groups such as Firmicutes, Bacteroidetes, Verrucomicrobia, Urovircota, and Proteobacteria. Our workflow involved RNA and DNA extraction, library preparation, assembly, and annotation, yielding valuable insights into gene discovery, microbial composition, and further genome and microbial function studies. In conclusion, our findings have significant implications for understanding the adaptive mechanisms of this species in response to environmental changes.


Assuntos
Metagenômica , Sciuridae , Transcriptoma , Animais , Bactérias/genética , Bactérias/classificação , Ecossistema , Metagenoma , Microbiota , Sciuridae/genética , Mongólia
10.
Ecol Evol Physiol ; 97(1): 53-63, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38717368

RESUMO

AbstractMany animals follow annual cycles wherein physiology and behavior change seasonally. Hibernating mammals undergo one of the most drastic seasonal alterations of physiology and behavior, the timing of which can have significant fitness consequences. The environmental cues regulating these profound phenotypic changes will heavily influence whether hibernators acclimate and ultimately adapt to climate change. Hence, identifying the cues and proximate mechanisms responsible for hibernation termination timing is critical. Northern Idaho ground squirrels (Urocitellus brunneus)-a rare, endemic species threatened with extinction-exhibit substantial variation in hibernation termination phenology, but it is unclear what causes this variation. We attached geolocators to free-ranging squirrels to test the hypothesis that squirrels assess surface conditions in spring before deciding whether to terminate seasonal heterothermy or reenter torpor. Northern Idaho ground squirrels frequently reentered torpor following a brief initial emergence from hibernacula and were more likely to do so earlier in spring or when challenged by residual snowpack. Female squirrels reentered torpor when confronted with relatively shallow snowpack upon emergence, whereas male squirrels reentered torpor in response to deeper spring snowpack. This novel behavior was previously assumed to be physiologically constrained in male ground squirrels by testosterone production required for spermatogenesis and activated by the circannual clock. Assessing surface conditions to decide when to terminate hibernation may help buffer these threatened squirrels against climate change. Documenting the extent to which other hibernators can facultatively alter emergence timing by reentering torpor after emergence will help identify which species are most likely to persist under climate change.


Assuntos
Hibernação , Sciuridae , Estações do Ano , Neve , Animais , Sciuridae/fisiologia , Hibernação/fisiologia , Feminino , Masculino , Torpor/fisiologia
11.
Gen Comp Endocrinol ; 354: 114541, 2024 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-38685390

RESUMO

The measurement of glucocorticoid (GC) hormones provides us with a window into the stress physiology of vertebrates and the adaptative responses they use to cope with predictable and unpredictable changes in the environment. Baseline GCs inform us about the metabolic demands they are subject to at that point in their yearly life-history stage, whereas GC changes (often increases) in response to acute challenges inform us on their capacity to cope with more immediate environmental challenges. However, baseline GC levels and the kinetics of GC responses to acute stressors can vary substantially among and within species, depending on individual characteristics (age, sex, condition, life-history stage). In addition, a thorough understanding of the stress status of an animal requires moving beyond the measurement of GCs alone by focusing on downstream measures of metabolic activation, such as oxidative stress. Here, we evaluated the changes in blood cortisol and oxidative stress markers in wild adult Columbian ground squirrels (Urocitellus columbianus), following a 30-min capture-handling stress performed in mid-late June. Measurements were taken when males were post-reproductive and preparing for hibernation and adult females were weaning litters. We found three key results. First, the time-course of GC increase was markedly slower (by an order of magnitude) than what is currently reported in the literature for most species of mammals, birds and reptiles. Second, there were marked differences in the male and female response, linked to differences in life-history stage: females close to weaning had abolished GC responses, whereas post-reproductive males did not. Third, there were mild to moderate increases in oxidative damage and decreases in oxidative defenses in response to our short-term challenge, consistent with the idea that short-term acute metabolic activation may carry physiological costs. However, these changes were not correlated to the changes in GCs, a novel result suggesting a disconnect between the hormonal stress response and oxidative damage.


Assuntos
Estresse Fisiológico , Animais , Feminino , Masculino , Estresse Fisiológico/fisiologia , Estresse Oxidativo/fisiologia , Hidrocortisona/metabolismo , Hidrocortisona/sangue , Glucocorticoides/metabolismo , Sciuridae/fisiologia
12.
PLoS One ; 19(4): e0298756, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38630730

RESUMO

Wireless Sensor Networks (WSNs) consist of small, multifunctional nodes distributed across various locations to monitor and record parameters. These nodes store data and transmit signals for further processing, forming a crucial topic of study. Monitoring the network's status in WSN applications using clustering systems is essential. Collaboration among sensors from various domains enhances the precision of localised information reporting. However, nodes closer to the data sink consume more energy, leading to hotspot challenges. To address these challenges, this research employs clustering and optimised routing techniques. The aggregation of information involves creating clusters, further divided into sub-clusters. Each cluster includes a Cluster Head (CH) or Sensor Nodes (SN) without a CH. Clustering inherently optimises CHs' capabilities, enhances network activity, and establishes a systematic network topology. This model accommodates both multi-hop and single-hop systems. This research focuses on selecting CHs using a Genetic Algorithm (GA), considering various factors. While GA possesses strong exploration capabilities, it requires effective management. This research uses Prairie Dog Optimization (PDO) to overcome this challenge. The proposed Hotspot Mitigated Prairie with Genetic Algorithm (HM-PGA) significantly improves WSN performance, particularly in hotspot avoidance. With HM-PGA, it achieves a network lifetime of 20913 milliseconds and 310 joules of remaining energy. Comparative analysis with existing techniques demonstrates the superiority of the proposed approach.


Assuntos
Algoritmos , Sciuridae , Animais , Análise por Conglomerados
13.
Proc Biol Sci ; 291(2021): 20232681, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38654643

RESUMO

Early-life adversity, even when transient, can have lasting effects on individual phenotypes and reduce lifespan across species. If these effects can be mitigated by a high-quality later-life environment, then differences in future resources may explain variable resilience to early-life adversity. Using data from over 1000 wild North American red squirrels, we tested the hypothesis that the costs of early-life adversity for adult lifespan could be offset by later-life food abundance. We identified six adversities that reduced juvenile survival in the first year of life, though only one-birth date-had continued independent effects on adult lifespan. We then built a weighted early-life adversity (wELA) index integrating the sum of adversities and their effect sizes. Greater weighted early-life adversity predicted shorter adult lifespans in males and females, but a naturally occurring food boom in the second year of life ameliorated this effect. Experimental food supplementation did not replicate this pattern, despite increasing lifespan, indicating that the buffering effect of a future food boom may hinge on more than an increase in available calories. Our results suggest a non-deterministic role of early-life conditions for later-life phenotype, highlighting the importance of evaluating the consequences of early-life adversity in the context of an animal's entire life course.


Assuntos
Longevidade , Sciuridae , Animais , Masculino , Feminino , Sciuridae/fisiologia
14.
Vet Parasitol Reg Stud Reports ; 50: 101014, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38644045

RESUMO

The present pilot research was focused on the detection of intestinal parasites in the ground squirrel populations in various regions of Slovakia. Only a very little information is currently available on the parasitic species composition of the European ground squirrel in Slovakia and across Europe. In the Slovak Republic, there are 70 locations where the ground squirrel populations are present. A total of 600 faecal samples of the European ground squirrels, collected from 36 locations all over Slovakia, were examined by applying the coprological method. The presence of the protozoan coccidian parasite of the Eimeria genus was confirmed in all of the analysed locations. The presence of eggs of four helminths were confirmed: Capillaria spp. (66.6% of locations); the Trichostrongylidae family (42.8% of locations); Hymenolepis spp. (11.9% of locations); and Citellina spp. (7.14% of locations). Dead individuals that were found in the analysed localities were subjected to necropsy and the tissues scraped off their small intestines were stained in order to confirm the presence of parasites. The post-mortem examination of the intestines and the sedimentation of the intestinal contents in a saline solution did not result in the confirmation of the presence of the eggs, adults or the larval stages of parasites. Spermophilus citellus is one of the strictly protected animal species in Slovakia. In recent years, numerous projects aimed at supporting and protecting ground squirrels have been implemented. The present pilot study on intestinal parasites and the subsequent cooperation with environmental activists will contribute to the support and stabilisation of the presence of these animals in our country.


Assuntos
Espécies em Perigo de Extinção , Fezes , Enteropatias Parasitárias , Sciuridae , Animais , Sciuridae/parasitologia , Eslováquia/epidemiologia , Enteropatias Parasitárias/veterinária , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Fezes/parasitologia , Doenças dos Roedores/parasitologia , Doenças dos Roedores/epidemiologia , Projetos Piloto , Eimeria/isolamento & purificação , Eimeria/classificação
16.
Lab Anim (NY) ; 53(5): 117-120, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38637688

RESUMO

Many research groups explore the regulation of hibernation or compare the physiology of heterothermic mammals between the torpid and aroused, euthermic states. Current methods for monitoring torpor (for example, infrared cameras, body temperature or heart-rate telemetry, and motion sensing) are costly, require specialized techniques, and can be invasive. Here we present an alternate method for determining torpor-bout duration that is cost-effective, noninvasive and accurate: paper towel shredding. In the winter, euthermic thirteen-lined ground squirrels will shred paper towels placed in the cage, but torpid animals will not. The presence of a shredded paper towel, indicating an arousal from torpor, is easily evaluated during routine daily monitoring. In 12 animals over 52 days, this simple technique detected 59 arousals with 100% accuracy when compared with the body temperature telemetry of the same animals. Moreover, this novel method avoids some of the drawbacks of other cheap monitoring systems such as the sawdust technique.


Assuntos
Hibernação , Sciuridae , Animais , Sciuridae/fisiologia , Hibernação/fisiologia , Nível de Alerta/fisiologia , Telemetria/métodos , Telemetria/veterinária , Temperatura Corporal , Masculino , Papel , Abrigo para Animais
17.
Ticks Tick Borne Dis ; 15(4): 102341, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38593668

RESUMO

The nidicolous tick Ixodes laguri is a nest-dwelling parasite of small mammals that mainly infest rodents of the families Cricetidae, Gliridae, Muridae and Sciuridae. There is no proven vectorial role for I. laguri, although it is suggested that it is a vector of Francisella tularensis. In this study, a first map depicting the entire geographical distribution of I. laguri based on georeferenced locations is presented. For this purpose, a digital data set of 142 georeferenced locations from 16 countries was compiled. Particular attention is paid to the description of the westernmost record of I. laguri in the city of Vienna, Austria. There, I. laguri is specifically associated with its main hosts, the critically endangered European hamster (Cricetus cricetus) and the European ground squirrel (Spermophilus citellus). These two host species have also been mapped in the present paper to estimate the potential distribution of I. laguri in the Vienna metropolitan region. The range of I. laguri extends between 16-108∘ E and 38-54∘ N, i.e. from Vienna in the east of Austria to Ulaanbaatar, the capital of Mongolia. In contrast to tick species that are expanding their range and are also becoming more abundant as a result of global warming, I. laguri has become increasingly rare throughout its range. However, I. laguri is not threatened by climate change, but by anthropogenic influences on its hosts and their habitats, which are typically open grasslands and steppes. Rural habitats are threatened by the intensification of agriculture and semi-urban habitats are increasingly being destroyed by urban development.


Assuntos
Distribuição Animal , Ixodes , Infestações por Carrapato , Animais , Áustria , Ixodes/crescimento & desenvolvimento , Ixodes/fisiologia , Infestações por Carrapato/veterinária , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Espécies em Perigo de Extinção , Sciuridae/parasitologia , Cricetinae , Doenças dos Roedores/parasitologia , Doenças dos Roedores/epidemiologia
18.
J Am Assoc Lab Anim Sci ; 63(3): 251-256, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38453171

RESUMO

Due to a lack of evidence-based standards for cage-change intervals for antelope ground squirrels (AGS, Ammospermophilus leucurus), we evaluated cage ammonia accumulation in our colony of adult, wild-caught AGS and identified factors that influenced ammonia levels. Intracage ammonia was measured daily in singly housed AGS in static caging that contained a running wheel and 1/2, 3/4, 1, or 2 quart (qt) of corncob bedding. Cages were changed when ammonia levels reached greater than 50ppm, our upper acceptable limit for ammonia based on mouse studies of ammonia aversion and toxicity. We also measured average daily water consumption over 2 wk to examine any correlation between water use and ammonia accumulation. We hypothesized that the desert-dwelling AGS would not reach intracage ammonia levels of greater than 50ppm in a 2-wk interval at any bedding volume. Our data showed that intracage ammonia was highly variable among individuals and was significantly associated with water consumption and bedding volumes. Seventeen percent of AGS on 1/2qt of bedding and 18% on 3/4qt of bedding reached greater than 50ppm ammonia before 7 d. All AGS on 1 and 2qt of bedding remained below 50ppm ammonia for 1 wk. Even when maintained on 2qt of bedding, not all AGS remained below 50ppm ammonia for 2 wk. Therefore, we concluded that the most appropriate option was weekly cage change for singly housed AGS on 1qt of bedding in static caging.


Assuntos
Amônia , Abrigo para Animais , Sciuridae , Animais , Amônia/análise , Sciuridae/fisiologia , Feminino , Masculino , Ingestão de Líquidos , Criação de Animais Domésticos/métodos , Bem-Estar do Animal
19.
J Anim Ecol ; 93(6): 663-675, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38494654

RESUMO

Mathematical models highlighted the importance of pathogen-mediated invasion, with the replacement of red squirrels by squirrelpox virus (SQPV) carrying grey squirrels in the UK, a well-known example. In this study, we combine new epidemiological models, with a range of infection characteristics, with recent longitudinal field and experimental studies on the SQPV dynamics in red and grey squirrel populations to better infer the mechanistic basis of the disease interaction. A key finding is that a model with either partial immunity or waning immunity and reinfection, where individuals become seropositive on the second exposure to infection, that up to now has been shown in experimental data only, can capture the key aspects of the field study observations. By fitting to SQPV epidemic observations in isolated red squirrel populations, we can infer that SQPV transmission between red squirrels is significantly (4×) higher than the transmission between grey squirrels and as a result our model shows that disease-mediated replacement of red squirrels by greys is considerably more rapid than replacement in the absence of SQPV. Our findings recover the key results of the previous model studies, which highlights the value of simple strategic models that are appropriate when there are limited data, but also emphasise the likely complexity of immune interactions in wildlife disease and how models can help infer disease processes from field data.


Assuntos
Infecções por Poxviridae , Sciuridae , Animais , Sciuridae/virologia , Sciuridae/imunologia , Sciuridae/fisiologia , Reino Unido/epidemiologia , Infecções por Poxviridae/veterinária , Infecções por Poxviridae/transmissão , Infecções por Poxviridae/virologia , Infecções por Poxviridae/imunologia , Infecções por Poxviridae/epidemiologia , Doenças dos Roedores/virologia , Doenças dos Roedores/transmissão , Doenças dos Roedores/imunologia , Doenças dos Roedores/epidemiologia , Modelos Biológicos , Poxviridae/fisiologia , Poxviridae/imunologia , Espécies Introduzidas
20.
Sci Rep ; 14(1): 5204, 2024 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-38433273

RESUMO

Species-habitat associations are correlative, can be quantified, and used for powerful inference. Nowadays, Species Distribution Models (SDMs) play a big role, e.g. using Machine Learning and AI algorithms, but their best-available technical opportunities remain still not used for their potential e.g. in the policy sector. Here we present Super SDMs that invoke ML, OA Big Data, and the Cloud with a workflow for the best-possible inference for the 300 + global squirrel species. Such global Big Data models are especially important for the many marginalized squirrel species and the high number of endangered and data-deficient species in the world, specifically in tropical regions. While our work shows common issues with SDMs and the maxent algorithm ('Shallow Learning'), here we present a multi-species Big Data SDM template for subsequent ensemble models and generic progress to tackle global species hotspot and coldspot assessments for a more inclusive and holistic inference.


Assuntos
Acesso à Informação , Big Data , Animais , Aprendizado de Máquina , Algoritmos , Sciuridae
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...